Managing Directory Listings

Seagull gives access to some nice PEAR utilities for managing directory listings. Basically using PEAR's File::Util located in SGL_Util you can:

• list files or directories in one line of code
• filter the results
• tranform the results

The latter two features are achieved using callback functions, here's an example of all of the above:

/***
 * Various utility methods.
 *
 * @package SGL
 * @author  Demian Turner <demian@phpkitchen.com>
 * @version $Revision: 1.12 $
 * @since   PHP 4.1
 */
class SGL_Util
{
    //  other methods left of for clarity
    
    function getAllNavDrivers()
    {
        SGL::logMessage(null, PEAR_LOG_DEBUG);

        require_once 'File/Util.php';
        $navDir = SGL_MOD_DIR . '/navigation/classes';

        //  match files with *Nav.php format
        $ret = SGL_Util::listDir($navDir, FILE_LIST_FILES, $sort = FILE_SORT_NONE, 
                create_function('$a', 'return preg_match("/.*Nav\.php/", $a);'];

        //  parse out filename w/o extension and .
        array_walk($ret, create_function('&$a', 'preg_match("/^.*Nav/", $a, $matches); $a =  $matches[0]; return true;'];
        return $ret;
    }

    /**
     * Wrapper for the File_Util::listDir method.
     * 
     * Instead of returning an array of objects, it returns an array of
     * strings (filenames).
     * 
     * The final argument, $cb, is a callback that either evaluates to true or
     * false and performs a filter operation, or it can also modify the 
     * directory/file names returned.  To achieve the latter effect use as 
     * follows:
     * 
     * <code>
     * function uc(&$filename) {
     *     $filename = strtoupper($filename);
     *     return true;
     * }
     * $entries = File_Util::listDir('.', FILE_LIST_ALL, FILE_SORT_NONE, 'uc');
     * foreach ($entries as $e) {
     *     echo $e->name, "\n";
     * }
     * </code>
     * 
     * @static
     * @access  public
     * @return  array
     * @param   string  $path
     * @param   int     $list
     * @param   int     $sort
     * @param   mixed   $cb
     */
    function listDir($path, $list = FILE_LIST_ALL, $sort = FILE_SORT_NONE, $cb = null)
    {
        $aFiles = File_Util::listDir($path, $list, $sort, $cb);
        $aRet = array();
        foreach ($aFiles as $oFile) {
            $aRet[$oFile->name] = $oFile->name;
        }
        return $aRet;
    }
}